Submission #986845

#	Time	Username	Problem	Language	Result	Execution time	Memory
986845		GrindMachine	Friend (IOI14_friend)	C++17	100 / 100	21 ms	4332 KiB

friend

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

using namespace std;
using namespace __gnu_pbds;

template<typename T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
typedef long long int ll;
typedef long double ld;
typedef pair<int,int> pii;
typedef pair<ll,ll> pll;

#define fastio ios_base::sync_with_stdio(false); cin.tie(NULL)
#define pb push_back
#define endl '\n'
#define sz(a) (int)a.size()
#define setbits(x) __builtin_popcountll(x)
#define ff first
#define ss second
#define conts continue
#define ceil2(x,y) ((x+y-1)/(y))
#define all(a) a.begin(), a.end()
#define rall(a) a.rbegin(), a.rend()
#define yes cout << "Yes" << endl
#define no cout << "No" << endl

#define rep(i,n) for(int i = 0; i < n; ++i)
#define rep1(i,n) for(int i = 1; i <= n; ++i)
#define rev(i,s,e) for(int i = s; i >= e; --i)
#define trav(i,a) for(auto &i : a)

template<typename T>
void amin(T &a, T b) {
    a = min(a,b);
}

template<typename T>
void amax(T &a, T b) {
    a = max(a,b);
}

#ifdef LOCAL
#include "debug.h"
#else
#define debug(x) 42
#endif

/*

refs:
edi

*/

const int MOD = 1e9 + 7;
const int N = 10 + 5;
const int inf1 = int(1e9) + 5;
const ll inf2 = ll(1e18) + 5;

#include "friend.h"

int findSample(int n, int a[], int host[], int protocol[]){
	vector<pll> val(n);
	rep(i,n) val[i].ff = a[i];
	rev(i,n-1,1){
		auto &[p1,q1] = val[host[i]];
		auto &[p2,q2] = val[i];
		if(protocol[i] == 0){
			// IAmYourFriend
			p1 = p1+q2;
			q1 = max(q1+p2,q1+q2);
		}
		else if(protocol[i] == 1){
			// MyFriendsAreYourFriends
			p1 = max({p1+q2,p2+q1,p1+p2});
			q1 = q1+q2;
		}
		else{
			// WeAreYourFriends
			p1 = max(p1+q2,p2+q1);
			q1 = q1+q2;
		}
	}

	ll ans = max(val[0].ff,val[0].ss);
	return ans;
}

• Subtask 1: 11 / 11
• Subtask 2: 8 / 8
• Subtask 3: 8 / 8
• Subtask 4: 19 / 19
• Subtask 5: 23 / 23
• Subtask 6: 31 / 31